Measurement of the Positive Muon Anomalous Magnetic Moment to 0.46 ppm

We present the first results of the Fermilab National Accelerator Laboratory (FNAL) Muon g-2 Experiment for the positive muon magnetic anomaly a_{μ}≡(g_{μ}-2)/2. The anomaly is determined from the precision measurements of two angular frequencies. Intensity variation of high-energy positrons from muon decays directly encodes the difference frequency ω_{a} between the spin-precession and cyclotron frequencies for polarized muons in a magnetic storage ring. The storage ring magnetic field is measured using nuclear magnetic resonance probes calibrated in terms of the equivalent proton spin precession frequency ω[over ˜]_{p}^{'} in a spherical water sample at 34.7 °C. The ratio ω_{a}/ω[over ˜]_{p}^{'}, together with known fundamental constants, determines a_{μ}(FNAL)=116 592 040(54)×10^{-11} (0.46 ppm). The result is 3.3 standard deviations greater than the standard model prediction and is in excellent agreement with the previous Brookhaven National Laboratory (BNL) E821 measurement. After combination with previous measurements of both μ^{+} and μ^{-}, the new experimental average of a_{μ}(Exp)=116 592 061(41)×10^{-11} (0.35 ppm) increases the tension between experiment and theory to 4.2 standard deviations.

Nonmonotonic Energy Dependence of Net-Proton Number Fluctuations

Nonmonotonic variation with collision energy (sqrt[s_{NN}]) of the moments of the net-baryon number distribution in heavy-ion collisions, related to the correlation length and the susceptibilities of the system, is suggested as a signature for the quantum chromodynamics critical point. We report the first evidence of a nonmonotonic variation in the kurtosis times variance of the net-proton number (proxy for net-baryon number) distribution as a function of sqrt[s_{NN}] with 3.1  σ significance for head-on (central) gold-on-gold (Au+Au) collisions measured solenoidal tracker at Relativistic Heavy Ion Collider. Data in noncentral Au+Au collisions and models of heavy-ion collisions without a critical point show a monotonic variation as a function of sqrt[s_{NN}].

Improved multiplex TaqMan qPCR assay with universal internal control offers reliable and accurate detection of Clavibacter michiganensis

AIM

Clavibacter michiganensis (Cm) is a seed-borne plant pathogen that significantly reduces tomato production worldwide. Due to repeated outbreaks and rapid spread of the disease, seeds/transplants need to be certified free of the pathogen before planting. To this end, we developed a multiplex TaqMan qPCR assay that can accurately detect Cm in infected samples.

METHODS AND RESULTS

A specific region of Cm (clvG gene) was selected for primer design using comparative genomics approach. A fully synthetic universal internal control (UIC) was also designed to detect PCR inhibitors and false-negative results in qPCRs. The Cm primers can be used alone or in a triplex TaqMan qPCR assay with UIC and previously described Clavibacter primers. The assay was specific for Cm and detected up to 10 fg of Cm DNA in sensitivity and spiked assays. Addition of the UIC did not change the specificity or sensitivity of the multiplex TaqMan qPCR assay.

CONCLUSION

The triplex TaqMan qPCR provides a specific and sensitive diagnostic assay for Cm.

SIGNIFICANCE AND IMPACT OF THE STUDY

This assay can be used for biosecurity surveillance, routine diagnostics, estimating bacterial titres in infected material and for epidemiological studies. The UIC is fully synthetic, efficiently amplified and multiplex compatible with any other qPCR assay.

Aerosol-induced atmospheric heating rate decreases over South and East Asia as a result of changing content and composition

Aerosol emissions from human activities are extensive and changing rapidly over Asia. Model simulations and satellite observations indicate a dipole pattern in aerosol emissions and loading between South Asia and East Asia, two of the most heavily polluted regions of the world. We examine the previously unexplored diverging trends in the existing dipole pattern of aerosols between East and South Asia using the high quality, two-decade long ground-based time series of observations of aerosol properties from the Aerosol Robotic Network (AERONET), from satellites (Moderate Resolution Imaging Spectroradiometer (MODIS) and Ozone Monitoring Instrument (OMI)), and from model simulations (Modern-Era Retrospective Analysis for Research and Applications, version 2 (MERRA-2). The data cover the period since 2001 for Kanpur (South Asia) and Beijing (East Asia), two locations taken as being broadly representative of the respective regions. Since 2010 a dipole in aerosol optical depth (AOD) is maintained, but the trend is reversed—the decrease in AOD over Beijing (East Asia) is rapid since 2010, being 17% less in current decade compared to first decade of twenty-first century, while the AOD over South Asia increased by 12% during the same period. Furthermore, we find that the aerosol composition is also changing over time. The single scattering albedo (SSA), a measure of aerosol’s absorption capacity and related to aerosol composition, is slightly higher over Beijing than Kanpur, and has increased from 0.91 in 2002 to 0.93 in 2017 over Beijing and from 0.89 to 0.92 during the same period over Kanpur, confirming that aerosols in this region have on an average become more scattering in nature. These changes have led to a notable decrease in aerosol-induced atmospheric heating rate (HR) over both regions between the two decades, decreasing considerably more over East Asia (− 31%) than over South Asia (− 9%). The annual mean HR is lower now, it is still large (≥ 0.6 K per day), which has significant climate implications. The seasonal trends in AOD, SSA and HR are more pronounced than their respective annual trends over both regions. The seasonal trends are caused mainly by the increase/decrease in anthropogenic aerosol emissions (sulfate, black carbon and organic carbon) while the natural aerosols (dust and sea salt) did not change significantly over South and East Asia during the last two decades. The MERRA-2 model is able to simulate the observed trends in AODs well but not the magnitude, while it also did not simulate the SSA values or trends well. These robust findings based on observations of key aerosol parameters and previously unrecognized diverging trends over South and East Asia need to be accounted for in current state-of-the-art climate models to ensure accurate quantification of the complex and evolving impact of aerosols on the regional climate over Asia.

Fragility of a soliton's shot-to-shot coherence

We show that a soliton in a high-order spatial mode of a multi-mode fiber can completely lose its shot-to-shot coherence due to a noise seed with energy orders of magnitude below that of the soliton. The total degradation of shot-to-shot coherence is caused by a very strong recently demonstrated intermodal nonlinear effect, soliton self-mode conversion. The results indicate that the robustness of solitons against perturbations is not entirely applicable in the presence of intermodal nonlinearities, and, more generally, that certain single-mode results cannot be trivially extrapolated to multi-mode fibers.

Inter-annual and seasonal variations in columnar aerosol characteristics and radiative effects over the Pokhara Valley in the Himalayan foothills - Composition, radiative forcing, and atmospheric heating

This study reports comprehensive analysis of seasonal and inter-annual variations of aerosol properties (optical, physical and chemical) and radiative effects over Pokhara Valley in the foothills of central Himalayas in Nepal utilizing the high-quality multi-year columnar aerosol data observed recently from January 2010 to December 2017. This paper focusses on the seasonal and inter-annual variations of chemical (composition), and absorption properties of aerosols and their radiative effects. The single scattering albedo (SSA) either decreases as a function of wavelength or remains independent of wavelength. The seasonal mean aerosol absorption optical depth (AAOD) exhibits a behavior opposite to that of SSA. Carbonaceous aerosols (CA) dominate (≥60%) aerosol absorption during the whole year. Black carbon (BC) alone contributes >60% to AAOD_CA while brown carbon (BrC) shares the rest. The absorbing aerosol types are determined to be BC, and mixed (BC and dust) only. Dust as absorbing aerosol type is absent over the Himalayan foothills. The ARF_SFC is ≥ -50 Wm^-2 except in monsoon almost every year. The ARF_ATM is ≥ 50 Wm^-2 during winter and pre-monsoon in all the years. ARFE_SFC, ARFE_TOA and ARFE_ATM follow a similar pattern as that of ARF. High values of ARFE at SFC, TOA and ATM (except during monsoon when values are slightly lower) suggest that aerosols are efficient in significantly modulating the incoming solar flux throughout the year. The annual average aerosol-induced atmospheric heating rate (HR) over Pokhara is nearly 1 K day^-1 every year during 8-year observation, and is highest in 2015 (∼2.5 K day^-1). The HR is about 1 K day^-1 or more over all the locations in IGP during the year. These quantitative results can be used as inputs in global/regional climate models to assess the climate impact of aerosols, including on regional temperature, hydrological cycle and melting of glaciers and snowfields in the region.

Black carbon dominates the aerosol absorption over the Indo-Gangetic Plain and the Himalayan foothills

This study, based on new and high quality in situ observations, quantifies for the first time, the individual contributions of light-absorbing aerosols (black carbon (BC), brown carbon (BrC) and dust) to aerosol absorption over the Indo-Gangetic Plain (IGP) and the Himalayan foothill region, a relatively poorly studied region with several sensitive ecosystems of global importance, as well as highly vulnerable populations. The annual and seasonal average single scattering albedo (SSA) over Kathmandu is the lowest of all the locations. The SSA over Kathmandu is < 0.89 during all seasons, which confirms the dominance of light-absorbing carbonaceous aerosols from local and regional sources over Kathmandu. It is observed here that the SSA decreases with increasing elevation, confirming the dominance of light absorbing carbonaceous aerosols at higher elevations. In contrast, the SSA over the IGP does not exhibit a pronounced spatial variation. BC dominates (≥75%) the aerosol absorption over the IGP and the Himalayan foothills throughout the year. Higher BC concentration at elevated locations in the Himalayas leads to lower SSA at elevated locations in the Himalayas. The contribution of dust to aerosol absorption is higher throughout the year over the IGP than over the Himalayan foothills. The aerosol absorption over South Asia is very high, exceeding available observations over East Asia, and also exceeds previous model estimates. This quantification will be valuable as observational constraints to help improve regional simulations of climate change, impacts on the glaciers and the hydrological cycle, and will help to direct the focus towards BC as the main contributor to aerosol-induced warming in the region.

Circulation of Asian-I and Cosmopolitan genotypes of Dengue-2 virus in northeast India, 2016-2017

BACKGROUND & OBJECTIVES

Dengue is a major public health problem in northeast India where the majority of the cases go unreported and undiagnosed. Even though all four dengue serotypes are reported, there is a dearth of information on genetic diversity. The present cross-sectional study was undertaken during 2016-17 to determine the genetic variance of dengue virus serotype 2 (DENV-2) based on the envelope (E) glycoprotein gene.

METHODS

The serum samples collected from the northeast parts of India, as a part of hospital-based acute febrile illness surveillance, were serotyped. Viral RNA was extracted from DENV-2 serum samples using QIAquick® RNA Extraction Kit. The E gene was amplified by conventional reverse-transcriptase polymerase chain reaction (RT-PCR) and the PCR products were sequenced.

RESULTS

The E glycoprotein gene of nine serum samples with high viral RNA concentration (Ct <25) was sequenced. The E gene sequences of eight DENV-2 strains from Assam and Meghalaya aligned with genotype IV (Cosmopolitan) and one strain from Tripura segregated with Asian-I genotype.

INTERPRETATION & CONCLUSION

Ongoing laboratory-based surveillance is mandatory to understand the transmission dynamics of dengue in endemic countries. This study concluded that in northeast India, presently two distinct genotypes of DENV-2, namely genotype IVb (Cosmopolitan) and Asian-I genotype are in circulation.

A junior doctor's experience of critical illness: from treating patients to becoming a patient with COVID-19

When the coronavirus disease 2019 (COVID‐19) pandemic was declared, it was clear that severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) would have far‐reaching impacts on medicine, society and everyday life. As a junior doctor working closely with patients with SARS‐CoV‐2 infection, I was aware of my personal risk of exposure to the virus. I assumed that as a fit and well 26‐year‐old with no comorbidities, if I were to become infected, it was unlikely that COVID‐19 would be severe. However, I became critically unwell following a week of clinical work, necessitating hospital admission, tracheal intubation and mechanical ventilation. I remained mechanically ventilated for 6 days and was then transferred to a medical ward 2 days later. After two further days of rehabilitation, I was discharged home. This reflection is not a junior doctor’s view of how COVID‐19 was managed by the NHS, but a personal view of my illness from ‘the other side of the curtain’. My reflections focus upon the psychological aspects of my experiences, exploring the memories that I formed around the time of critical care, how the fears that I possessed were managed with exceptional communication, and the importance of the wider healthcare team in my recovery.

First Measurement of Λ_{c} Baryon Production in Au+Au Collisions at sqrt[s_{NN}]=200 GeV

We report on the first measurement of the charmed baryon Λ_{c}^{±} production at midrapidity (|y|<1) in Au+Au collisions at sqrt[s_{NN}]=200  GeV collected by the STAR experiment at the Relativistic Heavy Ion Collider. The Λ_{c}/D^{0} [denoting (Λ_{c}^{+}+Λ_{c}^{-})/(D^{0}+D[over ¯]^{0})] yield ratio is measured to be 1.08±0.16  (stat)±0.26  (sys) in the 0%-20% most central Au+Au collisions for the transverse momentum (p_{T}) range 3<p_{T}<6  GeV/c. This is significantly larger than the pythia model calculations for p+p collisions. The measured Λ_{c}/D^{0} ratio, as a function of p_{T} and collision centrality, is comparable to the baryon-to-meson ratios for light and strange hadrons in Au+Au collisions. Model calculations including coalescence hadronization for charmed baryon and meson formation reproduce the features of our measured Λ_{c}/D^{0} ratio.

Rapid Synthesis and Characterization of Pure and Cobalt Doped Zinc Aluminate Nanoparticles via Microwave Assisted Combustion Method

Zn_1-xCo_xAl₂O₄ (0 ≤ x ≤ 0.5) nanoparticles were synthesized employing L-alanine as fuel using MACT (microwave assisted combustion technique). The synthesized samples were characterized following methods such as X-ray Diffraction, high resolution scanning electron microscopy, Energydispersive X-ray spectroscopy; UV-visible diffused reflectance spectroscopy, FT-IR and VSM. The XRD confirmed the cubic spinel structure and the average crystallite size observed lying in the range of 12-19 nm deduced using the Debye Scherrer's equation. The morphology of the Zn_1-xCo_xAl₂O₄ (0 ≤ x ≤ 0.5) nanoparticles is observed using HR-SEM. EDX analysis is opted for the elemental mapping of pure and cobalt doped zinc aluminate nanoparticles. Further band gap value was calculated using Kubelka Munk function, which was seen lying within 3.73 to 5.45 eV. The strong absorption band at 669, 556 and 500 cm^-1 was associated with the vibrations of Zn-O, Al-O and Zn-O-Al of zinc aluminate nanoparticles. The hysteresis loops exhibited conversion from diamagnetic into super paramagnetic behaviour with increase in Co doping.

Predictors for 30-day mortality and complications following radiologically inserted gastrostomies: a single centre, large cohort review

AIM

To measure the 30-day mortality and delayed complication rates following radiologically inserted gastrostomy (RIG) placement and determine the predictive risk factors for 30-day mortality and delayed complications to aide pre-procedure informed consent.

MATERIALS AND METHODS

Retrospective analysis was undertaken of RIG insertions between July 2012 and August 2017 at a single tertiary centre, which included 373 patients (56% male; median age: 65 years, range: 19-92 years). Data were collected from electronic databases on patient demographics, RIG indication, all-cause mortality, complication rates, patient co-morbidities, and biochemical/haematological parameters. Multivariate analysis was performed to identify predictive risk factors for complications and mortality.

RESULTS

The RIG procedural success rate was 97.9%. The overall 30-day mortality rate was 7.8%; associated with pre-procedural haemoglobin <130 g/l in men (p=0.030, odds ratio [OR] 23.38), white cell count >11×10⁹/l (p=0.001, OR 4.18), C-reactive protein >10 mg/l (p=0.003, OR 10.10) and international normalised ratio (INR) >1.2 (p=0.03, OR 4.63). Inpatient RIG referrals were associated with 10% 30-day mortality; compared to 1.1% for outpatients (p=0.028, OR 9.51). The incidence of immediate and delayed complications was 2.4% and 42.1%, respectively. Neuromuscular disease was associated with gastrostomy dislodgement (p=0.0001, OR 4.99) and fracture (p=0.0009, OR 13.45), cerebrovascular disease with gastrostomy dislodgement (p=0.009, OR 2.51), cardiovascular disease with sepsis 30-days post-RIG (p=0.02, OR 2.94), and diabetes mellitus with gastrostomy dislodgement (p=0.0001, OR 29.45), fracture (p=0.027, OR 5.63) and stoma site infections (p=0.0003, OR 7.16).

CONCLUSION

RIG 30-day mortality was significantly associated with inpatient procedures compared to outpatient, and a range of biochemical/haematological parameters that suggest infection pre-intervention. It is advised that the markers of infection and catabolism are investigated pre-intervention, which may reduce mortality and complication rates.

First Observation of the Directed Flow of D^{0} and D^{0}[over ¯] in Au+Au Collisions at sqrt[s_{NN}]=200 GeV

We report the first measurement of rapidity-odd directed flow (v_{1}) for D^{0} and D^{0}[over ¯] mesons at midrapidity (|y|<0.8) in Au+Au collisions at sqrt[s_{NN}]=200  GeV using the STAR detector at the Relativistic Heavy Ion Collider. In 10-80% Au+Au collisions, the slope of the v_{1} rapidity dependence (dv_{1}/dy), averaged over D^{0} and D^{0}[over ¯] mesons, is -0.080±0.017(stat)±0.016(syst) for transverse momentum p_{T} above 1.5  GeV/c. The absolute value of D^{0} meson dv_{1}/dy is about 25 times larger than that for charged kaons, with 3.4σ significance. These data give a unique insight into the initial tilt of the produced matter, and offer constraints on the geometric and transport parameters of the hot QCD medium created in relativistic heavy-ion collisions.

Polarization of Λ (Λ[over ¯]) Hyperons along the Beam Direction in Au+Au Collisions at sqrt[s_{NN}]=200 GeV

The Λ (Λ[over ¯]) hyperon polarization along the beam direction has been measured in Au+Au collisions at sqrt[s_{NN}]=200  GeV, for the first time in heavy-ion collisions. The polarization dependence on the hyperons' emission angle relative to the elliptic flow plane exhibits a second harmonic sine modulation, indicating a quadrupole pattern of the vorticity component along the beam direction, expected due to elliptic flow. The polarization is found to increase in more peripheral collisions, and shows no strong transverse momentum (p_{T}) dependence at p_{T} greater than 1  GeV/c. The magnitude of the signal is about 5 times smaller than those predicted by hydrodynamic and multiphase transport models; the observed phase of the emission angle dependence is also opposite to these model predictions. In contrast, the kinematic vorticity calculations in the blast-wave model tuned to reproduce particle spectra, elliptic flow, and the azimuthal dependence of the Gaussian source radii measured with the Hanbury Brown-Twiss intensity interferometry technique reproduce well the modulation phase measured in the data and capture the centrality and transverse momentum dependence of the polarization signal.

Observation of Excess J/ψ Yield at Very Low Transverse Momenta in Au+Au Collisions at sqrt[s_{NN}]=200 GeV and U+U Collisions at sqrt[s_{NN}]=193 GeV

We report on the first measurements of J/ψ production at very low transverse momentum (p_{T}<0.2  GeV/c) in hadronic Au+Au collisions at sqrt[s_{NN}]=200  GeV and U+U collisions at sqrt[s_{NN}]=193  GeV. Remarkably, the inferred nuclear modification factor of J/ψ at midrapidity in Au+Au (U+U) collisions reaches about 24 (52) for p_{T}<0.05  GeV/c in the 60%-80% collision centrality class. This noteworthy enhancement cannot be explained by hadronic production accompanied by cold and hot medium effects. In addition, the dN/dt distribution of J/ψ for the very low p_{T} range is presented for the first time. The distribution is consistent with that expected from the Au nucleus and shows a hint of interference. Comparison of the measurements to theoretical calculations of coherent production shows that the excess yield can be described reasonably well and reveals a partial disruption of coherent production in semicentral collisions, perhaps due to the violent hadronic interactions. Incorporating theoretical calculations, the results strongly suggest that the dramatic enhancement of J/ψ yield observed at extremely low p_{T} originates from coherent photon-nucleus interactions. In particular, coherently produced J/ψ's in violent hadronic collisions may provide a novel probe of the quark-gluon plasma.

Global Text Mining and Development of Pharmacogenomic Knowledge Resource for Precision Medicine

Understanding patients’ genomic variations and their effect in protecting or predisposing them to drug response phenotypes is important for providing personalized healthcare. Several studies have manually curated such genotype–phenotype relationships into organized databases from clinical trial data or published literature. However, there are no text mining tools available to extract high-accuracy information from such existing knowledge. In this work, we used a semiautomated text mining approach to retrieve a complete pharmacogenomic (PGx) resource integrating disease–drug–gene-polymorphism relationships to derive a global perspective for ease in therapeutic approaches. We used an R package, pubmed.mineR, to automatically retrieve PGx-related literature. We identified 1,753 disease types, and 666 drugs, associated with 4,132 genes and 33,942 polymorphisms collated from 180,088 publications. With further manual curation, we obtained a total of 2,304 PGx relationships. We evaluated our approach by performance (precision = 0.806) with benchmark datasets like Pharmacogenomic Knowledgebase (PharmGKB) (0.904), Online Mendelian Inheritance in Man (OMIM) (0.600), and The Comparative Toxicogenomics Database (CTD) (0.729). We validated our study by comparing our results with 362 commercially used the US- Food and drug administration (FDA)-approved drug labeling biomarkers. Of the 2,304 PGx relationships identified, 127 belonged to the FDA list of 362 approved pharmacogenomic markers, indicating that our semiautomated text mining approach may reveal significant PGx information with markers for drug response prediction. In addition, it is a scalable and state-of-art approach in curation for PGx clinical utility.

Azimuthal Harmonics in Small and Large Collision Systems at RHIC Top Energies

The first (v_{1}^{fluc}), second (v_{2}), and third (v_{3}) harmonic coefficients of the azimuthal particle distribution at midrapidity are extracted for charged hadrons and studied as a function of transverse momentum (p_{T}) and mean charged particle multiplicity density ⟨N_{ch}⟩ in U+U (sqrt[s_{NN}]=193  GeV), Au+Au, Cu+Au, Cu+Cu, d+Au, and p+Au collisions at sqrt[s_{NN}]=200  GeV with the STAR detector. For the same ⟨N_{ch}⟩, the v_{1}^{fluc} and v_{3} coefficients are observed to be independent of the collision system, while v_{2} exhibits such a scaling only when normalized by the initial-state eccentricity (ϵ_{2}). The data also show that ln(v_{2}/ϵ_{2}) scales linearly with ⟨N_{ch}⟩^{-1/3}. These measurements provide insight into initial-geometry fluctuations and the role of viscous hydrodynamic attenuation on v_{n} from small to large collision systems.

Octave-wide supercontinuum generation of light-carrying orbital angular momentum

Nonlinear frequency generation of light-carrying orbital angular momentum (OAM), which facilitates realization of on-demand, frequency-diverse optical vortices, would have utility in fields such as super-resolution microscopy, space-division multiplexing and quantum hyper-entanglement. In bulk media, OAM beams primarily differ in spatial phase, so the nonlinear overlap integral for self-phase matched χ⁽³⁾ processes remains the same across the 4-fold degenerate subspace of beams (formed by different combinations of spin and orbital angular momentum) carrying the same OAM magnitude. This indistinguishable nature of nonlinear coupling implies that supercontinuum generation, which substantially relies on self/cross-phase modulation, and Raman soliton shifting of ultrashort pulses typically results in multimode outputs that do not conserve OAM. Here, using specially designed optical fibers that support OAM modes whose group velocity can be tailored, we demonstrate Raman solitons in OAM modes as well as the first supercontinuum spanning more than an octave (630 nm to 1430 nm), with the entire spectrum in the same polarization as well as OAM state. This is fundamentally possible because spin-orbit interactions in suitably designed fibers lead to large effective index and group velocity splitting of modes, and this helps tailoring nonlinear mode selectivity such that all nonlinearly generated frequencies reside in modes with high spatial mode purity.

Fate of a Soliton in a High Order Spatial Mode of a Multimode Fiber

We show numerically that under certain conditions noise-induced soliton self-mode conversion dominates over soliton self-frequency shift for a soliton in a high order spatial mode of a multimode optical fiber. The input soliton has to be group index matched to a lower order mode for a frequency separation for which the Raman gain is non-negligible, and this condition determines the wavelength of the pulse growing from noise. The phenomenon has no known analogs in single-mode or graded-index fibers. The results demonstrate that it is possible for a noise-induced physical process to dominate over a seeded one even for noise levels at the fundamental limit.